8029075: String deduplication in G1
Summary: Implementation of JEP 192, http://openjdk.java.net/jeps/192
Reviewed-by: brutisso, tschatzl, coleenp
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#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1STRINGDEDUPTHREAD_HPP
#define SHARE_VM_GC_IMPLEMENTATION_G1_G1STRINGDEDUPTHREAD_HPP
#include "gc_implementation/g1/g1StringDedupStat.hpp"
#include "gc_implementation/shared/concurrentGCThread.hpp"
//
// The deduplication thread is where the actual deduplication occurs. It waits for
// deduplication candidates to appear on the deduplication queue, removes them from
// the queue and tries to deduplicate them. It uses the deduplication hashtable to
// find identical, already existing, character arrays on the heap. The thread runs
// concurrently with the Java application but participates in safepoints to allow
// the GC to adjust and unlink oops from the deduplication queue and table.
//
class G1StringDedupThread: public ConcurrentGCThread {
private:
static G1StringDedupThread* _thread;
G1StringDedupThread();
~G1StringDedupThread();
void print(outputStream* st, const G1StringDedupStat& last_stat, const G1StringDedupStat& total_stat);
public:
static void create();
static G1StringDedupThread* thread();
virtual void run();
virtual void print_on(outputStream* st) const;
};
#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1STRINGDEDUPTHREAD_HPP